Do You Want Your Images To Look Good On Your Blog?
I have always been uploading my images to my blogs using the .jpg format BUT Blogger.com also lets you to be able to choose a .png and .bmp format as well. However I would advise you not to upload your photos or images in the .bmp format only because that format will result in a bigger size.
I found out that if I upload my images using the .png format then they look a LOT clearer than they look when I upload them using the .jpg format.
And just in case you're wondering what 2d graphics program that I use to convert my images to the .png format - I use the Windows Paint program!